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December 9: Playtime Party @ Saint, 90 Exeter Street,Boston, MA November 22, 2010

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December 9: Playtime Party @ Saint, 90 Exeter Street,Boston, MA

Playtime!

Thursday, December 9, 2010

Saint

90 Exeter Street, Boston, MA 02116

Cover: Say “playtime” at the door. Cover is $5.00 at the door, FREE with the Playtime Mobile coupon found in the Peekaboo Mobile & WHERE Apps.

Contact: playtimeboston@gmail.com

Remember:

1. Say “playtime” at the door

2. A strict “No Work” policy will be in full effect

3. You must be 21+ to attend

Boxborough’s Lightower Fiber Networks acquires Westford’s Veroxity Technology Partners, for undisclosed terms October 4, 2010

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Boxborough’s Lightower Fiber Networks, a provider of fiber network and broadband services, acquires Westford, Massachusetts -based Veroxity Technology Partners, a provider of fiber based data and internet connectivity solutions, for undisclosed terms.

Mass Innovation Night Tonight at Waltham’s IBM Innovation Center at 6:30pm — FREE! February 17, 2010

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Massachusetts Innovation Night tonight at Waltham’s (MA) IBM Innovation Center, 404 Wyman Street. Companies launching include: Alphasoftware, Hubcast, Kaon Interactive, Onstate, Scallop Imaging and VisibleGains. Meet author Steve Garfield and experts from 406 Ventures, Brainshark and Jetty Marketing. Starts at 6:30pm. Park in North Garage. FREE!

2009 Dice Technology & Engineering Career Fair in Boston Thursday, December 10: 11am-3pm Marriott Burlington November 24, 2009

Posted by HubTechInsider in events, Staffing & Recruiting.
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2009 Dice Technology & Engineering Career Fair Boston: Event at Marriott Burlington, Burlington, MA

Thursday, December 10

11 a.m. to 3 p.m.

Marriott Boston Burlington • Rt 128 & 3A (One Mall Road) • Burlington, MA 01803

Admission is FREE

Meet recruiters and hiring managers from these companies: Cambridge Interactive Development Corp., e-Dialog, •Raytheon, Research In Motion, Tufts Health Plan.

Register for this event online by clicking here!

Entrepreneurship and Innovation in 2009 and Beyond: Massachusetts vs. Silicon Valley (MP3) November 20, 2009

Posted by HubTechInsider in events, Staffing & Recruiting, Technology, Venture Capital.
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This is a Stereo MP3 audio transcription of the excellent presentation that was given this morning by Ronald Croen, Founder, former CEO and Chairman of Nuance Communications, who is now Tufts University’s Entrepreneur-in-Residence for 2009-2010. The talk was given at IBM’s Waltham Innovation Center, in Waltham, Massachusetts.

Ronald Croen, a co-founder of Nuance, has served as Chairman of the Board of Nuance Communications. Croen held the positions of President and CEO of Nuance from July 1994 – March 2003. Previously, he served as a consultant to SRI International, an independent research, technology development and consulting organization, for the commercialization of its speech recognition capability. From 1987 to 1989, Croen served as Managing Director of European Operations, and from 1983 to 1987 as Vice President and General Counsel of The Ultimate Corp. Croen holds a J.D. degree from the University of Pennsylvania Law School and a B.A. from Tufts University.

The topic of the presentation was:

Entrepreneurship and Innovation in 2009 and Beyond: Massachusetts vs. Silicon Valley

091120_004 [mp3 raw file – click to listen on most computers]

091120_004 – Ronald A. Croen [Imeem Hosted Stream]

(This mp3 Stereo Audio Recording is a large file, and you may want to save it directly to your computer’s hard disk drive for listening – you can do so by right-clicking on the filename, above, and using the ‘save link as…’ option)

I had a wonderful opportunity to meet and speak with Bobbie Carlton, the founder of Massachusetts Innovation Nights at the Charles River Museum of Industry in Waltham, and I want to take the opportunity here to thank her for her efforts in arranging this new breakfast Massachusetts Innovation gathering. I think some thanks also go to the gracious corporate host, IBM, whose Waltham Innovation Center is truly an impressive facility; I enjoyed their tour of the facility after Mr. Croen’s presentation.

There was a terrific question-and-answer session with the attendees at the conclusion of the presentation which featured a lively debate and brought up some fascinating points; I recommend you listen to this towards the end of the mp3 audio transcription.

There are some great videos of Ron Croen’s presentation available here.

Massachusetts Innovation Breakfast Friday, 20 November at 8:30am at the IBM Innovation Center in Waltham – Ronald Croen, CEO of Nuance, will be speaking November 19, 2009

Posted by HubTechInsider in events, VUI Voice User Interface.
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Massachusetts Innovation Breakfast kicks off this week with a Friday morning (8:30 a.m.- 10:00 a.m.) casual get-together at the IBM Innovation Center in Waltham.

There’s limited space so sign up now. (You must RSVP by the end of the business day Thursday to be part of the group.)

There will be a chance to look around the IBM Innovation Center, and there will be a special guest speaker, Ronald Croen, Founder, CEO and Chairman of Nuance Communications, who will be speaking on Entrepreneurship and Innovation in 2009 and Beyond: Massachusetts vs. Silicon Valley.

There is a Stereo mp3 audio transcription of this presentation, as well as the excellent question-and-answers session which followed, posted on this site below:

Entrepreneurship and Innovation in 2009 and Beyond: Massachusetts vs. Silicon Valley – Ronald A. Croen

There are some great videos of Ron Croen’s presentation available here.

Westford, MA based wireless video technology company Aylus Networks Inc raises $5.7 Million in a Series C round of equity financing November 17, 2009

Posted by HubTechInsider in Mobile Software Applications, Telecommunications, Venture Capital, Wireless Applications.
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Westford, MA based wireless video technology company Aylus Networks Inc raises $5.7 Million in a Series C round of equity financing from a number of undisclosed institutional investors.

Mass Innovation Nights November event to be held tonight at the Charles River Museum of Industry in Waltham, MA November 11, 2009

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Many of you know I support and regularly attend, among many other startup and technology networking groups in the area, Mass Innovation Nights in Waltham. I recommend you come out to the event tonight, and I look forward to seeing you there and at the after party at Biagio’s, one of my favorite Moody Street Waltham restaurants (and there are alot of them!)

Mass Innovation Nights is a FREE monthly product launch party and networking event held every month at the Charles River Museum of Industry & Innovation:

154 Moody Street
Waltham, MA 02453

Wednesday, Nov 11 (TONIGHT)

— Doors open at 6:00
— Demos start at 6:30

After-party 8:30 pm
Biagio’s Plush Lounge
123 Moody St.

The following companies will be exhibiting this evening:

Conversion Associates
Implementation Factory
Lime Design
Magic Toob
Risk-wise Investor
Teenlife
Textaurant
Think Flood
Utest
V.i. Labs

What is Cao’s Law? June 11, 2009

Posted by HubTechInsider in Definitions, Fiber Optics, Telecommunications.
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Cao’s Law states that the communications spectrum is virtually infinite and that WDM (Wave Division Multiplexing) will allow the information transmitted upon the available spectrum to expand exponentially as the growth of transistors in Moore’s Law. Using less and less power, WDM will allow finer and finer channels of light to transmit more and more data. Cao’s Law states that these lambdas will expand at a rate two to three times the rate of expansion of transistors on an integrated circuit chip as in Moore’s Law. On optical fibers, as opposed to the tradeoffs between power and connectivity in the transistor world, in the optical realm, the tradeoff is between bitrate and channel count. To this point of the technology’s development, we can either pump a high bitrate on each channel or we can transmit lots of channels, but we cannot do both of these things at the same time. Among telecom carriers today, there seems to be a manifestation of Simon Cao’s Law in action in the real world.

SS7 – Signaling System Seven – Telecommunications Protocol SS7 June 10, 2009

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SS7 software layers

SS7 software layers

In Signaling System 7 (SS7) protocol, a worldwide standard (with variations), routing intelligence is located in low cost computer-based equipment rather than in central office switches.

One of the primary benefits of SS7 is global interoperability. It has the capability to enable all carriers to cooperate with each other. It is a standard protocol approved by the ITU. Global billing, toll-free calling, 900-number services, and international wireless call roaming are all call features that are dependent on SS7.

SS7 is used on a global basis. In North America, the ANSI version of SS7 is used. In Europe, the ETSI version is used. In other pats of the world, the ITU version of SS7 is used.

Gateways allow these international SS7 implementations to communicate with each other.

SS7 is essential to modern networking. With SS7, an overlaid packet switched network controls the underlying voice network’s operation and signaling information is carried on a separate channel from voice and data traffic.

Because signaling is such a quick network activity, it is possible to multiplex many signaling messages over one signaling channel using a packet switching arrangement.

SS7 permits the telephone company to provide one database for several switches in order to freeup switch capability for other functions. This is the capability that makes SS7 the foundation for Intelligent Networks (INs) as well as Advanced Intelligent Networks (AINs).

As an example, in order to provide a service such as 900 number and toll-free calling, in SS7, powerful parallel processing computer systems hold massive databases with information such as routing instructions for toll-free and 900 number telephone calls. One processor with its database supports many central office switches under SS7. in this way, each central office itself is not required to host the centralized database. Without the need to share the expense of maintaining the sophisticated routing information, each central office can share in the expense of a database or feature upgrade to the centralized SS7 datastore.

MCI first implemented SS7 into its network in 1988. SS7 enabled them to halve their call setup time on calls between Philadelphia and Los Angeles. Freeing up voice channels from their previous signaling duties pre-SS7 enabled carriers to pack more voice calls on their existing network paths.

Cellular networks use SS7 technology to support roaming. Every cellular provider has a database called the home location register, or HLR, where complete information regarding each subscriber is kept. They also maintain a database called the VLR, or visitor location register, that maintains information on each caller who visits from other areas. When a cellular subscriber roams, each network they visit exchanges SS7 messages with their “home” network. The subscriber’s home system also marks its HLR so that it knows where to send calls for its customers who are roaming.

SS7 has three major components:

1. Packet switches – Signal Transfer Points that route signals between databases and central switches. STPs, or Signal Transfer Points, are responsible for translating the SS7 messages and then routing these messages amongst the various network nodes and databases. Signal Transfer points are packet switches that route signals between central offices as specialized databases. Messages are sent between points on the SS7 network in variable-length packets with the addresses attached. Signal transfer switches read only the address portion of the packets and forward the messages accordingly.

2. Service Switching Points – Software and ports in central offices that enable switches to query databases. SSPs are the switches that begin and end calls. They receive signals from the Customer Provided Equipment (CPE) and then process the calls on the behalf of the end users. The user triggers the network to provide various services by dialing particular digits. SSPs are typically implemented at access tandem offices, local exchanges or toll centers that contain the needed network signaling protocols. The SSP serves as the begining and ending point for SS7 messaging.

3. Service Control Points – DBs with customer feature and billing information. Service Control Points, or SCPs, interface with SSPs as well as STPs. The STP contains the network configuration and call-completion database – the SCP contains all the service logic that is needed to deliver the type of call and feature in the call that the user is requesting. SCPs are centralized network nodes that contain software and databases needed for call management. Functions such as digit translation, call routing and verification of credit cards are all provided by SCPs. Usually a SCP will receive traffic from a SSP via the STP and will then return responses based on those queries by way of the STP.

The SS7 signaling data link is a full duplex digital transmission channel that operates at either 56 Kbs (T-Carrier transmission systems, in North America) or 64 Kbps (E_Carrier transmission systems, Europe). SS7 also defines a number of other types of links, each with a specific use within a SS7 network.

A (access) links
B (bridge) links, D (diagonal) links, and B/D links
C (cross) links
E (extended) links
F (fully associated) links

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You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. I have been working in the software engineering and ecommerce industries for over fifteen years. My interests include computers, electronics, robotics and programmable microcontrollers, and I am an avid outdoorsman and guitar player. You can connect with me on LinkedIn, follow me on Twitter, follow me on Quora, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m a Technical PMO Director, I’m a serial entrepreneur and the co-founder of several ecommerce and web-based software startups, the latest of which are Twitterminers.com and Tshirtnow.net.

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The Advantages and Disadvantages of Fiber Optics June 4, 2009

Posted by HubTechInsider in Fiber Optics, Telecommunications.
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English: A TOSLINK fiber optic cable with a cl...

English: A TOSLINK fiber optic cable with a clear jacket that has a laser being shone onto one end of the cable. The laser is being shone into the left connector; the light coming out the right connector is from the same laser. (Photo credit: Wikipedia)

Advantages of fiber optics:

1. Extremely high bandwidth – No other cable-based data transmission medium offers the bandwidth that fiber does.

2. Easy to accomodate increasing bandwidth – Using many of the recent generations of fiber optic cabling, new equipment can be added to the inert fiber cable that can provide vastly expanded capacity over the originally laid fiber. DWDM, or Dense Wavelength Division Multiplexing, lends fiber optic cabling the ability to turn various wavelengths of light traveling down the fiber on and off at will. These two characteristics of fiber cable enable dynamic network bandwidth provisioning to provide for data traffic spikes and lulls.

3. Resistance to electromagnetic interference – Fiber has a very low rate of bit error (10 EXP-13), as a result of fiber being so resistant to electromagnetic interference. Fiber-optic transmission are virtually noise free.

4. Early detection of cable damage and secure transmissions – Fiber provides an extremely secure transmission medium, as there is no way to detect the data being transmitted by “listening in” to the electromagnetic energy “leaking” through the cable, as is possible with traditional, electron-based transmissions. By constantly monitoring an optical network and by carefully measuring the time it takes light to reflect down the fiber, splices in the cable can be easily detected.

Disadvantages of Fiber Optics:

1. Installation costs, while dropping, are still high – Despite the fact that fiber installation costs are dropping by as much as 60% a year, installing fiber optic cabling is still relatively costly. As installation costs decrease, fiber is expanding beyond its original realm and major application in the carrier backbone and is moving into the local loop, and through technologies such as FTTx (Fiber To The Home, Premises, etc,) and PONs (Passive Optical networks), enabling subscriber and end user broadband access.

2. Special test equipment is often required – The test equipment typically and traditionally used for conventional electron-based networking is of no use in a fiber optic network. Equipment such as an OTDR (Optical Time Domain Reflectometer)

is required, and expensive, specialized optical test equipment such as optical probes are needed at most fiber endpoints and connection nexuses in order to properly provide testing of optical fiber.

3. Susceptibility to physical damage – Fiber is a small and compact cable, and it is highly susceptible to becoming cut or damaged during installation or construction activities. Because railroads often provide rights-of-way for fiber optic installation, railroad car derailments pose a significant cable damage threat, and these events can disrupt service to large groups of people, as fiber optic cables can provide tremendous data transmission capabilities. Because of this, when fiber optic cabling is chosen as the transmission medium, it is necessary to address restoration, backup and survivability.

4. Wildlife damage to fiber optic cables – Many birds, for example, find the Kevlar reinforcing material of fiber cable jackets particularly appealing as nesting material, so they peck at the fiber cable jackets to utilize bits of that material. Beavers and other rodents use exposed fiber cable to sharpen their teeth and insects such as ants desire the plastic shielding in their diet, so they can often be found nibbling at the fiber optic cabling. Sharks have also been known to damage fiber optic cabling by chomping on it when laid underwater, especially at the repeating points. There is a plant called the Christmas tree plant that treats fiber optic cable as a tree root and wraps itself around the cable so tightly that the light impulses traveling down the fiber are choked off.

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You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

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I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at Cartera Commerce, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

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What is the definition of a Next-Generation Network, or NGN? May 28, 2009

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The term next-generation network is a term that has become more and more prevalent in telecommunications-industry publications and in the general technology and news media. The term actually has a very specific meaning in the telecom industry that I would like to clarify:

The rapidly declining cost of bandwidth, combined with the easy availability of powerful and cheap microprocessor technology, has brought to the fore the economies of scale that packet switching combined with statistical multiplexing afford, provided that a solution can be found to latency and packet loss.

In order to answer these challenges, next-generation networks have at their core two overriding concepts. First of all, a next-generation network supports QoS (Quality of Service) while being a fundamentally high-speed packet-based network which can carry and route a myriad of broadband services, including multimedia, video, data and voice.

Secondly, a next-generation network serves as a common application platform for services and applications that a customer base can access from anywhere across the network as well as outside it.

What is the difference between Cellular and PCS? May 17, 2009

Posted by HubTechInsider in Definitions, Fiber Optics, Mobile Software Applications, Telecommunications, Uncategorized, VUI Voice User Interface, Wireless Applications.
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Cellular is dual-classified as being inclusive of both analog and digital networks. Cellular networks began with analog infrastructures, and over time migrated this infrastructure to digital. In a cellular network, depending upon your location throughout the world, the operation frequencies are 800MHz to 900MHz band. Cellular infrastructure is generally based on a macrocell architecture. Macrocells involve a coverage area with a diameter of around 8 miles, and because of this large coverage area, cellular operates at high power levels, in a range of .6 to 3 watts.

PCS is a more recent technology, and has been all digital since inception. As with cellular, depending upon where you are located in the world, the frequency band of operation is in the 1.8GHz to 2GHz band. Instead of cellular macrocells, PCS uses two different infrastructures, both microcell and picocell. As these names imply, the coverage areas of these architectures are smaller than macrocells, around 1 mile in diameter. As a result, PCS uses much lower power levels – 100 milliwatts.

So the key differences between PCS and cellular are the frequencies in which they operate, coverage areas of their different cell architectures, and the power levels each uses to transmit signals. They work essentially the same way, use the same types of network elements, and perform the same functions.

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The SONET and SDH Signal Hierarchy: How many T-1s are in an OC-1, OC-3, OC-12, or OC-48? May 10, 2009

Posted by HubTechInsider in Definitions, Fiber Optics, Telecommunications, Uncategorized.
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I have found that there exists out there in the wide world a touch of confusion when it comes to recognizing the different signal levels and transmission speeds associated with what is referred to in the telecom industry as digital hierarchies, the two most common of which are, in North America, the PDH and SDH, or SONET, hierarchies.

Throughout my work as a telecommunications enthusiast, a pastime of discovery which has kept me occupied ever since my teen years, and on through many of my professional pursuits, I have always served as a point of reference for others in regards to the various telecommunications signal levels as well as the transmission speeds that these levels in the hierarchies represent. The following is my rough attempt to put this information into one place that can serve as a reference for me and others:

SONET was developed to aggregate, or multiplex, circuit switched traffic such as T-1, (E-1 in Europe) T-3, and slower rates of data traffic from multiple sources on fiber-optic networks. SONET transports traffic at high speeds called OC (Optical Carrier). The international version of SONET is called the synchronous digital hierarchy (SDH). SDH carries traffic at synchronous transport mode speeds. Equipment interfaces make SONET and SDH speeds compatible with each other, so the same SONET switching equipment can be used for both OC and SDH speeds.

OC-1 operates at 52 Mbps and is equivalent to 28 DS-1s (same as a T-1) or 1 DS-3 (same as a T-3). OC-1 is generally used as customer access lines. Early-adopter types of customers such as universities, airports, financial institutions, large government agencies, and ISPs – use OC-1.

OC-3 operates at 155 Mbps and is equivalent to 84 DS-1s (same as a T-1) or 3 DS-3s (same as a T-3). OC-3 speeds are required by end users such as companies in the aerospace industry and high-tier ISPs.

OC-12 operates at 622 Mbps and is equivalent to 336 DS-1s (same as T-1) or 12 DS-3s. This is another capacity towards which high-tier ISPs are moving. It was originally deployed for the metropolitan area fiber rings built out across cities worldwide, although those rings are now moving to OC-48.

OC-48 operates at 2,488 Mbps and is equivalent to 1,344 DS-1s (same as a T-1) or 48 DS-3s (same as a T-3). This capacity has been deployed for backbone, or core, networks. Today the metropolitan area rings are moving from OC-48 to OC-192.

OC-192 operates at 9,953 Mbps and is equivalent to 5,376 DS-1s (same as a T-1) or 192 DS-3s (same as a T-3). OC-192 is in use for backbone networks.

OC-768 operates at 39,812 Mbps and is equivalent to 21,504 DS-1s (same as a T-1) or 768 DS-3s (same as a T-3). Use of OC-768 is very rare outside of testing or research networks due to the great expense of this transmission speed level.

At times, you may see OC levels such as OC-1c, OC-3c, OC-12c, etc. This is called concatenation, and it puts streams of data into one fat, or high-bandwidth, contiguous stream. For example, OC-1 speeds of 52 Mbps may be used to carry broadcast video. In this case, OC-1c, or concatenated OC-1, carries OC-1 streams back-to-back. These streams travel contiguously through the network as long as capacity is available. Most applications for concatenation are high-speed data and broadcast-quality video.

As far as the DS, or Digital Signal Levels, of the older PDH, or Plesiochronous Digital Hierarchy (plesiochronous means “minute variations in timing”), they follow what is known as the T-carrier signal levels. Technically, the DS-x and CEPT-x terminology (DS-1, DS-3, CEPT-1, CEPT-3, and so on) indicates a specific signal level (and thus usable bandwidth), as well as the electrical interface specification. T-x and E-x terminology (T-1, T-3, E-1, E-3, and so on) indicates the type of carrier – a specific implementation of a DS-x/CEPT-x. More often than not these days, however, the terms DS-x and T-x are used interchangeably. So some people might use the term DS-1 and T-1 to refer to the same thing – a digital transport that can carry 1.544 Mpbs over a total of 24 voice channels. In Europe, the same is true: E-1 is the same as CEPT-1, and so forth.

A DS-0 (T-0) has a bit rate of 64 Kbps and carries 1 voice-grade channel.

A DS-1 is equivalent to a T-1 and has a bit rate of 1.544 Mpbs and carries 24 voice channels.

A DS-2 has a bit rate of 6.312 Mpbs and carries 96 voice channels, equivalent to 4 T-1s. This is also sometimes referred to as a T-2, or T2.

A DS-3 has a bit rate of 44.736 Mpbs and carries 672 voice channels, equivalent to 28 T-1s. This is also sometimes referred to as a T-3, or T3.

A DS-4 has a bit rate of 274.176 Mpbs and carries 4,032 voice channels, equivalent to 168 T-1s. This is also sometimes referred to as a T-4, or T4.


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You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.


About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

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Why IP beat out ATM for use in Next-Generation Voice Networks May 10, 2009

Posted by HubTechInsider in Telecommunications.
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For a good part of the 90’s, conventional wisdom in the telecommunications industry held that asynchronous transfer mode (ATM) and Internet Protocol (IP) were competing technologies. IP, the prevailing notion held, was a “best effort” service because IP-based networks indiscriminately discarded packets if there was congestion. There was no standardized protocol to identify and prioritize video and voice. The industry at that time maintained that best effort protocols would not be recognized by carriers as acceptable for voice traffic. Because of this, ATM’s ability to create virtual connections and to prioritize voice and video so that packets would never be dropped and quality of service standards were met gave ATM a vital advantage.

ATM also had speed advantages, capable of speeds of 155 and 622 megabits per second. Ethernet LANS at this time were limited to 10 megabits per second, and IP used between networks was also slower than ATM. For these above reasons, when carriers wanted to improve their networks, they decided on ATM equipment. I personally was involved in Fleet Bank’s multi-million dollar loan to LDDS Worldcom (now MCI) in the late nineties for ATM gear for their UUNET data network subsidiary.

However, despite all of its inherent advantages, ATM gear was costly and complex to install. There was a slight push around this time for ATM to be used in LANs, especially in campus backbone networks and NSF research nets, but ATM was far too expensive to deploy on the desktop. So ATM was relegated to use in large corporate backbone networks and carrier traffic-bearing data networking.

So, as you can imagine, mainly due to the speed and quality-of-service advantages, established telecom vendors and most new softswitch vendors initally at least based their next-generation voice switch architecture on ATM rather than IP. Meanwhile, improvements in routers and faster speeds on IP networks were making IP networks much more suitable for voice. Also at this time, Cisco’s TAG protocol, the forerunner of today’s MPLS, was being developed and was maturing. The MPLS protocol marked packets so that voice and video could be prioritized. This capability let IP packet flows be handled similarly to ATM virtual connections, which treat various types of traffic differently. Concurently, IP speeds improved from 10 megabits per second to 100 megabits per second speeds and, eventually, gigabit speeds.

With these notable improvements in speed and service qualities, along with the fact that corporate endpoints were already equipped to deal with IP traffic, the founders of Sonus Networks (Westford, MA), in 1997, choose to base their next-generation, softswitch-based voive infrastructure on IP. In this manner, Sonus was granted a head start over competitors who initially developed platforms based on ATM, losing time and previously invested development money when they switched over to IP – too late.

In related news, Sonus Networks of Westford, MA recently (11 March 09) announced it is “restructuring” again, cutting another 60 employees to complete its third round of cuts in three months. The company said this cut will equal out to about 6% of their workforce. The total job cuts within the three months has added up to 160 jobs lost at the networking equipment vendor. Sonus has a baseline resource level of approximately 1,000 people.

BT (British Telecom) has also recently (3 May 09) announced that it is cutting back on deployments of equipment and resources for its 21CN Next Generation Network (NGN) project.

Jefferies & Company analyst George Notter points out in a recent research note that Sonus was slated to in late 2007 to provide an Access Gateway Controller Function (AGCF) to enable communications between core IP and PSTN access networks. However, Sonus may have to take a revenue hit now, as BT discovered that its NGN network architecture is too costly. They have halted the NGN Network cutover project.

Update: Sonus Networks announces 2009 Q1 results

The transformative effect of Fiber Optics on Bandwidth May 7, 2009

Posted by HubTechInsider in Telecommunications.
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The stated figures you may frequently encounter for bandwidth measurements, expressed in bits per second, can be hard to interpret and grasp using real-world examples that can be easily envisioned. As a for instance, fiber optic transmission facilities and fiber cables can today very easily enable data transmission speeds of up to 10Gps. 10Gps transmission speeds mean 10 billion bits per second can be sent down the fiber – and this bandwidth can accommodate, as an example, sending all 32 volumes of the Encyclopedia Britannica in a mere tenth of a second.

But there is even more at work here; The real impact of fiber is not just on the ever advancing Bps rates that can be facilitated, but also in the capabilities fiber affords to us in terms of reducing the number of conversions from analog to digital that at present are required to traverse the legacy telecommunications infrastructure as the data moves from point to point across the globe.

A tectonic shift is occurring; The transition from the electronic era to the optical, or photonic era. An entirely new generation of switches and devices that at their heart are optical.

Consider the hypothetical example of a fax transmission from a location in the United States to a location in India. Beginning as marks on a piece of paper (the most analog of communications mediums), the fax machine in the US digitizes the paper’s marks (the first conversion). The modem in the fax machine then converts these digital bits into analog sounds that can be sent over the telephone. The Class 5 switch at the local exchange in the US converts these sounds back to digital (the third conversion). The Class 4 switch in the US then converts these digital bits back into analog for the trip overseas on the telephone network to India. The receiving Class 4 switch in India then converts these analog sounds back into digital bits. The Class 5 switch in India, close to the destination fax machine at the local exchange, then converts back into analog for the transmission to the receiving fax machine. The modem in the receiving fax machine then reconverts these analog sounds back into digital bits, which are assembled, checked for accuracy and printed on a blank sheet of paper, rendering a final analog page of marks exactly in the form of the marks on the original page that went into the US fax machine. That is a total of eight conversions! Avoiding this high number of conversions is possible only in an optical network; And when we have more optical equipment in the chain of network nodes, then we will be capable of utilizing fiber to an even greater degree to achieve previously unimagined transmission speeds.

Measuring Voice Quality in a VoIP environment May 1, 2009

Posted by HubTechInsider in Telecommunications, Uncategorized.
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One of the consequences of installing Voice over IP systems is that the “voice” sides of information technology departments are learning the lingo and technology of measuring voice quality on data networks. In addition, staffs that manage data networks are becoming aware of the criticality of voice. They are developing a cognizance of the impact on voice services of congestion when they add new applications. They also note lost voice service when they take down the network for maintenance or new installations.

Staff use network management tools that entail quality of service assesments to monitor the following factors in voice quality:

* Packet loss refers to the network dropping packets when there is congestion. Packet loss results in uneven voice quality. Voice conversations “break up” when packet loss is too high.

* Latency refers to delays when voice packets transverse the network. Latency is measured in milliseconds. It results in long pauses within conversations and clipped words.

* Jitter is uneven latency and packet loss resulting in noisy calls that contain pops and clicks or crackling sounds.

* Echo, hearing your voice repeated, is often caused when voice is translated from a circuit switched format to the IP format. This is usually corrected by special echo-canceling devices.

A brief, introductory telecommunications signaling tutorial April 30, 2009

Posted by HubTechInsider in Telecommunications.
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Signaling is the process of sending information between two parts of a network to control, route, and maintain a telephone call. For example, lifting the handset of a telephone from the receiver sends a signal to the central office: “I want to make a telephone call”. The central office sends a signal back to the user in the form of a dial tone, indicating that the network is ready to carry the call.
The three types of signals are as follows:

* Supervisory signals. Supervisory signals monitor the busy or idle condition of a telephone. They also are used to request service. They tell the central office when the telephone handset is lifted (off-hook requesting service) or hung up (on hook in the idle condition).

* Alerting signals. These are bell signals, tones, or strobe lights that alert end users that a call has arrived.

* Addressing signals. These are touch tones or data pulses that tell the network where to send the call. A compuer or person dialing a call sends addressing signals over the network.

Signals can be sent over the same channel as voice or data conversation or over a separate channel. Prior to 1976, all signals were sent over the same path as voice and data traffic. This is called in-band signaling. In-band signalling resulted in inefficient use of telephone lines. When a call was dialed, the network checked for an available path and tied up an entire path through the network before it sent the call through to the distant end. For example, a call from Miami to Los Angeles tied up a path throughout the network after the digits were dialed but before the call was started.

Prior to the proliferation of voice mail, between 20% and 35% of calls were incomplete due to busy signals, network congestion, and ring-no-answers. Therefore, channels that could be used for telephone calls were used to carry in-band signals such as those for incomplete calls, dial tone, and ringing. Multiplying this scenario by the millions of calls placed resulted in wasted telephone network facilities.

In addition to tying up telephone facilities, in-band signaling sets up calls more slowly than out-of-band signaling. To illustrate, the time between dialing an 800 call and hearing ring-back tones from the distant end is the call setup part of the call. Call setup includes dialing and waiting until the call is actually established.

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